Indoor Air Pollution in California

Report to the California Legislature INDOOR AIR POLLUTION IN CALIFORNIA A report submitted by: California Air Resources Board July, 2005 Pursuant to Health and Safety Code § 39930 (Assembly Bill 1173, Keeley, 2002)

Asbestos is a naturally occurring mineral fiber with strong commercial appeal due to its physical properties. It is a poor conductor, but a good insulator, and is strong, flexible, non-corrosive, and flame-resistant. Asbestos is a commercial term for a number of naturally occurring minerals: chrysotile belongs to the serpentine group, while amosite, crocidolite, tremolite, actinolite, and anthophyllite are in a group called amphiboles.

When inhaled, asbestos fibers penetrate deep into lung tissues where they cannot be expelled or destroyed by the body. Federal and international agencies recognize that asbestos is a carcinogen. In 1986, asbestos was identified as a toxic air contaminant under California’s Toxic Air Contaminants Program.

Exposure to asbestos is associated with increases in non-malignant respiratory symptoms, and may cause asbestosis, lung cancer, and mesothelioma. Indoor asbestos is primarily found in older homes in pipe and furnace insulation, shingles, millboard, textured paints and other coating materials, and floor tiles. Due to the success of remediation efforts, asbestos concentrations are generally quite low in most buildings today.